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大型工業吊扇(shan)運(yun)行(xing)在理想的(de)(de)情況(kuang)下(xia)，您可以把超大型工業風(feng)扇(shan)吹(chui)出的(de)(de)風(feng)想象成柱狀(zhuang)的(de)(de)氣(qi)(qi)流，柱狀(zhuang)氣(qi)(qi)流的(de)(de)外表面就(jiu)會與空氣(qi)(qi)產(chan)生摩擦(ca)，那 阻力=K1（阻力常數）*周長(chang) 通(tong)風(feng)量 =k2（速度常數）*截(jie)面積(ji)。拿(na)一個直徑 為 730mm的(de)(de)風(feng)扇(shan)和(he)直徑為 7300mm 的(de)(de)超做比較：  

1、直徑 730mm 的風扇：周(zhou)長=0.73 × 3.14=2 .29m 截面積=0.36 × 0.36 × 3.14=0.407 平方(fang)米

 2、直徑 7200mm 的(de)風扇(shan) ：周長=7.2 × 3.14=22.9m 截面積=3.6 × 3.6 × 3.14=40.7 平方米 

由(you)此(ci)可見(jian)，通過同樣面積的(de)氣流(liu)的(de)阻力是小(xiao)風扇的(de) 0.1 倍  

原理：大(da)的(de)(de)氣(qi)流流體(ti)運動(dong)所受的(de)(de)摩擦(ca)力相(xiang)對小，從而使大(da)風扇能夠驅(qu)動(dong)大(da)量的(de)(de)空(kong)(kong)氣(qi)卻比小風扇所需(xu)的(de)(de)能量相(xiang)對要(yao)少(shao)! 一旦空(kong)(kong)氣(qi)的(de)(de)慣性得到克服(fu)，大(da)量的(de)(de)空(kong)(kong)氣(qi)流動(dong)的(de)(de)自身動(dong)能使之只需(xu)很小的(de)(de)后續(xu)動(dong)力即可維持(chi)空(kong)(kong)氣(qi)的(de)(de)持(chi)續(xu)流動(dong)。而小型的(de)(de)風扇的(de)(de)氣(qi)流摩擦(ca)比較大(da)，能量大(da)部分都損耗在摩擦(ca)過程中。

The large industrial ceiling fan is ideally operated, and you can imagine the wind blown out by the Super large industrial fan as a columnar air flow, and the outer surface of the columnar air flow will rub against the air. That resistance = K1(resistance constant) * perimeter ventilation = K2(velocity constant) * cross-sectional area. Take a 730mm diameter fan and a 7300mm diameter super large industrial fan for comparison:
1, 730mm diameter fan: perimeter = 0.73 × 3.14 = 2. 29M cross-sectional area = 0.36 × 0.36 × 3.14 = 0.407 square meters
2, 7200mm diameter fan: perimeter = 7.2 × 3.14 = 22.9 M cross-sectional area = 3.6 × 3.6 × 3.14 = 40.7 square meters
It can be seen that the resistance of large fans passing through the same area of air flow is 0.1 times that of small fans.
Principle: The friction force of the large airflow fluid movement is relatively small, so that the large fan can drive a large amount of air but the energy required by the small fan is relatively less! Once the inertia of the air is overcome, the self-movement of a large amount of air flow can enable it to maintain the continuous flow of air with only a small amount of subsequent power. The friction of the small fan is relatively large, and most of the energy is lost during the friction process.